Externally-operated fuse and cut-out mechanism



Oct. 26 1926.

' G. E. PALMER ET AL EXTERNALLY OPERATED FUSE AND CUT-OUT MECHANISMFiled Feb. 21, 1925 2 Sheets-Sheet 1 $722076: gfflhmon.

Oct. 26 ,,1926., 1,604,191

G. E. PALMER ET AL EXTERNALLY OPERATED FUSEAAND CUT-OUT MECHANISM FiledFeb. 21, 1925 2 Sheets-Sheet 2 Patented Oct. 26, 1926.

EXTERNALLY-OPERATED FUSE AND CUT-OUT ME H-ANllsl i.

Application filed February 21, 1923. Serial No. 620,831.

This invention-relates to fuse and cut-out mechanisms of that typewherein all of the electrical current carrying parts are in an enclosurewhich by construction provides 5 either limited or complete access tothe members which normally form a part. of the electrical conductor.

Substantially all'electrical conductors supplying light and power areprovided with fuses or thermal cut-outs located at one or more points inthe premises in which the electric light or power is supplied. Theseconductors are normally enclosed except at the fuse from eitherintentional or accidental access for the purpose of protecting the occupants of the premises from the hazards present Where-electrifiedconductors may be touched.- But as it may be the business of a user ofelectric power to inspect or replace the fuse, this part of theconductor must by intention be made accessible and the design of theapparatus embodied in this invention is to provide means whereby in itsnormal assembled condition an operator is permitted to have access tothe fuse only when it is' disassociated from the conductor, theconstruction of the device being also such thatvby partial disassemblyan operator presumably skilled in handling electrified conductors mayhave access to the entire mechanism when electrified.

, It may be the business of those whoare unskilled in handlingelectrified conductors to inspect or replace electrical fuses and it maybe the business of those skilledin handling electrified conductors toexamine and if necessary repair electrified fuse mechanisms to correctconditions affecting the operation thereof and by the application ofthose construction details which are embodied in this invention ashereafter described, it will be evident to those skilled in the art thatit provides means which when intact permit inspection or replacement offuses only when they are disassociated from all electrified connectionsthat have a .difference of potential from earth, and also so constructedthat by a partial disassembly the entire mechanism may be inspected whenelectrified and operative.

We prefer to designate the device as a cutout mechanism to distinguishit from switch: ing mechanisms whichoperate to isolate the be passed toand from fuse from one portion of the electrical conductor, as, the fuseis disassociated from all parts of the electrical conductor when madeaccessible with the device in complete assembly as will be understoodfrom a more complete description of an embodiment thereof disclosed inthe accompanying drawings Figures 1 and 2 are front and side elevations,respectively, of the mechanism, the fuses being in operative relation tothe conductors.

Figures 3 and 4 are similar views showing the fuses disassociated fromthe conductors and exposed.

Figure 5 is a sectional detail on line 5-5 of igure 11, showing the fusemounting.

Figure 6 is a section on line 6 6 of Figurel.

Figure 7 is a detail section on line 77 of Figure 3. v

Figure 8 is a similar view, parts in different positions.

Figures 9 and 10 are detail side elevations but showing the of the fusesin ci cuit associated and disas-* sociated position, respectively, thepositions of certain portions of the casing being indicated by dottedlines. I

Figure 11 is a front elevation of the fuse carriers and related parts indisassociated position, the casing being shown in section. Figure 12 isa sectional detail of a fuse carrier.

Referring tothese figures at 1 is indicated a casing having side wallswhich may be provided with knock-outs as shown at 2 through whichconductors (not shown) may the mechanisms withm the casings. The casingmay also be provided with. an opening 3'in one side thereof which mayhouse the terminal portion of the meter. The particular details of thispart of the mechanism, however, are unimportant to the presentinvention, since they form no part thereof. The forward face of thecasing 1 is normally closed by a cover 6 which as shown is provided witha perforation for the reception of a lug 8 projecting from one side ofthe casing 1 and which is perforated for the reception of a seal of anysuitable description to prevent the unauthorized removal of the coverfrom the casing. This cover 6, however, is provided with one or tion 17fixed to the rear ,tact 16. Each sleeve -of one end of the casing moreapertures 9 of suitable size to permit the passage therethrough of fuses10, which 1 in the present instance are shown as of the plug type. Theseopenings 9 are normally bridged and closed by a closure or auxiharycover member 11 which as shown is hinged at 12 to the cover 6. When theauxiliary cover is closed, the fuses 10 are beneath the same andinaccessible, This closure 11 may, if desired, be provided with aperforated extension 13 which when the closure is in closed positionmates a similar projection 14 carried by the cover 6 and through which apadlock may be placed so that the closure 11 may be retained in closedposition to be opened only by persons authorizedto renew fuses and thelike, but who may not necessarily be authorized to remove the seal toopen the cover 6.

\Vithin'the casing is housed the terminal block and fuse carrier. At 15and .16 are shown stationary conductor terminals made fast to a terminalblock or base of insulaface of the casing 1. Extending from this base 17is a post 18, at the forward end of which is pivoted a carrier 5 towhich are fixed fuse blocks 19. Each block 19 has a flange portion 20 onits forward face which in one position of the carrier 5 bridges one'ofthe openings 9 of the cover 6. 1t constitutes an internal closuretherefor and, when closed, prevents access therethrou-gh to the liveparts within the casing. This internal closure is thus moved toward andfrom the front wall or cover of the casing as the switch is opened orclosed. Each block 19 as shown is provided with a plug socket consistingof a metallic threaded element 21 within which a plug fuse may bescrewed, this element 21 having in electrical connection therewith anarm 22 forming a movable terminal contact cooperating with the fixedcontact 15. Through the rear end of the block and centrally of thesleeve 21 is passed an insulating sleeve 23 through which is passed ascrew 24 which forms an electrical connection through the center of thesleeve 21 with an arm 25 which constitutes the movable terminal contactcooperating with the fixed con- 21 and screw 24 form fuse terminals fora fuse 10. By rocking the block 19, the arms 22 and 25 may be throwninto and out of engagement with the fixed contacts 15 and 16 tointer-pose or entirely remove the fuses from the electric circuitrespectively and thus to make or break electrical connection between theconductors 15 and 16. For swinging the carrier 5 an oscillating rockshaft 30 fixed thereto has been provided, which extends outwardly 1 andis there bent or formed into an operating lever handle 31. In order tolimit the rocking motion of this handle, it is formed with an extension32 which is bent out of nbmpf thereof to form a stop co-operating with aU-shaped retaining member 33 made fast to the end wall of the casing 1.The portion 32 extends housed by the closure 11. If the closure 11 isthen opened, the fuses project beyond the cover 6 where they may begrasped and turned so as to be removed from the block 19 and new fusessubstituted therefor without thenecessity of the hand extending withinany portion of the casing.

The fuses should be inaccessible for renewal when in connected position.For this urpose a locking means for the closure 11 as been provided,such means comprising a U-shaped latch member 40 sliding in a directionparallel to the axes of said auxiliary cover and the switch actuatingmeans and interlocking with said auxiliary cover and handle 31. Thismember is slidable through perforations 41 in one side wall of the cover6 and is retained on the rear face thereof by means of a bracket 42 madefast thereto. The inner side of the handle 3 when the switch is closedlies in the path of the latch member 40 so as to obstruct its movementand hold it in closure locking position. The closure 11 has fixedthereto an arm 43 which projects through a slot in the cover 6. and hastherein a perforation 44 through which the upper arm of the member 40may be projected when the closure is in closed position as shown inFigure 8. The portion 13 is also provided with an extension 130 whichwhen the closure 11 is closed projects into the casing throu h a slot131 in the cover 6, and is provide with a perforation 132 through whichthe lower arm of member 10 passes when the upper arm is projectedthrough the perforation 44. When the member 40 is retracted from theperforations 44 and 132 the closure 11 is free to be swung outwardlyabout its pivot 12, but when it has been so swung an imperforate portionofthe member 43 is in alinement with the latch so that this latch maynot be thrown into locking position. To prevent removal of the latch 40from the cover 6 one of the arms thereof may be perforated and receivetherethrough a cotter pin 45. As shown the outer end of the latch member40 is curved forwardly to form a handle portion 48 by which it may bereadily grasped. This handle Hill . the handle 48 may be pathintersecting the in such manner that ulled outwardly to release thelatch member only when the handle 31 is in the position at one end ofits path shown in Figure 4 when the fuses are disconnected from theconductors and are portion 48 moves in a path of the handle 31 projectedthrough the openings 9. If now the handle 48 is pulled outwardly asshown in Figure 3 to release the closure, the latch extends across thepath of the handle 31 so as to prevent the fuses from being thrown intoconnected position. The fuses therefore can not be connected with theconductors as long as the latch 40 is in closure unlocked position andthis latch may not be moved inwardly out of the Way of the handle 31until the closure 11 has been'brought down into position to house thefuses and render them normally inaccessible. When it has been so broughtdown the latch 40 may be moved to the end of its path to lockingposition whereupon the handle 31 may be thrown to connect the fuses tothe conductors. In this position, however, the latch 40 may not be movedto release the closure 11 the handle 31 lying across its ath.

It should be not however, that by breaking the seal fixing the cover 6in position, this cover may be removed carrying with it the closure 11and the latch member 40 without in any way affecting the relation of thefuses to the conductors. The entire electrical mechanism is thus exposedfor the purpose of inspection or; repair to one authorized to break theseal who is presumably competent to properly treat electrifiedmechanism, andit may be operated in the normal manner to connect ordisconnect the fuses from the conductors.

Having thus described an embodiment of this invention it should beevident to those skilled in the art that many changes and modificationsmight be made therein as defined by the appended claims.

We claim:

1. In a safety switch, the combination of,

a casing having side walls, a main cover scalable thereon and having anopening, a hinged auxiliary cover for said opening and a latch bothmounted on said main cover and removable therewith, a switch within saidcasing, a fuse and fuse terminals beneath said uxiliary cover whenclosed, and oscillating means extending through a side wall of saidcasing for actuating sald switch, said means comprising a lever handleexternal to said casing, said latch being movable independently of bothsaid auxilia cover and said handle and. interlocking t erewith so thatwhen either is locked the other is free and when either is free theother is locked, said cover when locked be' closed and said switch whensaid han open.

is locked being f in position to hold said fuse out of cones 2. Inaaafety switch, the combinationof a casing having side walls, a maincover scalable thereon and havin an opening spaced away from the top anbottom thereof, a hinged auxiliary cover for said open-r mg and amovable latch both mounted on said-main cover and removable therewith, a

ating said switch, said means comprising a lever handle-external to saidcasing and located opposite one end of said auxiliary cover and havingits inner side in the path of said latch whensaid switch and cover areclosed, saidlatch interloc with said auxiliary cover and handle so thatwhen either is locked the other is free and when either is free theother is locked, said cover when locked being closed and saidswitch-when said handle is locked being open.

3. In a safety switch,'the combination of a casing having side walls, amain cover scalable thereon and having an opening, a hinged auxiliarycover for said opening and a transversely slidable latch both mounted onsaid main cover and removable therewith, a switch within said casing, afuse and fuse terminals beneath said auxiliary cover when closed, andoscillating means extending through a side wall of said casing for.actuating said switch, said means com rising a lever handle external tosaid caslng, said latch interlockin with said auxiliary cover and handleso Slat when either is locked the other is free and when either is freethe other is locked, said cover when locked being closed and said switchwhen said handle is locked being open.

4. In combination with a casing havin an opening therein, a closure forsaid openmg, conductors and a fuse in said casing movable into and outof electrical connection with said conductors,rof a rocking member outaclosure except when said rocking member is of position in position toretain said fuseout of con nection with said conductors.

5. In combination with a casing having an opening therein, a closure forsaid opening, conductors and a fuse in said casing, of a rocking memberoutside of said casing for moving said fuse into and out of electricalconnection with said conductors, and,

a latch movable into and out of position to hold said closure in closedposition, said rocking member lying in the path of motion of sai latchto prevent unlocking of said closure except when said rockingmembe'r'jis -o enin a closure for said 0 enin tion with said conductors,and said latch projecting into the path of motion of said rocking memberto prevent said rocking member being moved to position to hold said fusein connection with said conductors except when said latch is in, lockingposit-ion.

6. In combination with a casing having an opening therein, a closure forsaid opening, conductors and a fuse in said casing movable into, and outof electrical connection with said conductors, of a rocking memberoutside of said casing for moving said fuse, a latch movable into andout of position to hold said closure in closed position, said rockingmember lying in the path of motion of said latch to prevent unlocking ofsaid closure except when said rocking member is in position to hold saidfuse out of connection with said conductors, and said latch projectinginto thev path of motion of said rocking member to prevent said rockingmember being moved to position to hold said fuse in connection with saidconductors ex cept when said latch is in locking position, and means forpreventing said latch from being moved to locking position except whensaid closure is closed.

7. In combination with a casing having an conductors and a fuse in saidcasing, of a movable member for holding said closure in closed position,and a movable member for moving said fuse into and out of electricalconnection with said conductors,

ment of said members intersecting in suc manner that each may be movedonly when.

the other is positioned at one end of its path.

8 In combination with a casing having an opening, a closure for saidopening, conductors and a fuse in said casing, of a movable member forholding said closure in closed position, and a movable member for movingsaid fuse into and out of electrical connection with said conductors,the paths of movement of said members intersect ng 1n the paths ofmovesuch manner that said holding member may be moved only when saidactuating member is in position to retain said fuse out of connectionwith said conductors and said actuating member may be moved only whensaid holding member is in position to retain said closure closed.

9. In combination with a casing havin an opening, a closure for saidopening, con uctors and a fuse in said casing, of a movable member forholding said closure in closed position, and a movable member for movingsaid fuse into and out of electrical connection with said conductors,both of said members being accessible from without said casing, thepaths of movement of said members intersecting in such manner that saidholding member may be moved only when said actuating member is inposition to hold said fuse out of connection with said conductors andsaid actuating member may be moved only when said holding member is' inposi tion to retain said closure closed.

10. In combination with 'acasing having an opening, a closure forsaid'opening, conductors and a fuse in said casing, of a movable memberfor holding said closure in clo:ed position, and a movable member formoving said fuse into and out of electrical connection with saidconductors, the paths of movement of said members intersecting in suchmanner that said holding member may be moved only when said actuatingmember is in position to hold said fuse out of contact with saidconductors and sa1d actuating member may be moved only when said holdingmember is in position to retain said closure closed, and means forpreventing movement of said holding member except when said closure isin closed position;

In testimony whereof we have affixed our signatures.

GRANVILLE E. PALMER. ERNEST e. JOHNSON.

